The ambitious Algerian program for diversification of electric energy sources is targeting 22 000 MWe from the renewable energy to the horizon of 2030. This study is a thermo-economic assessment of an integrated solar combined cycle system installed in the Saharan region, which during the nights or cloudy days works as a conventional combined cycle and does not need storage or back-up systems. The obtained results show, in one side that the solar electricity ratio may reach about 17 % and the global thermal efficiency up to 63 %, leading to lower fuel consumption and carbon emission. In the other side, the economic assessment depicts that the levelized cost of energy may reach a value of 0.0222 $/kWh which is about 28 % higher than CC plants. By considering the environment this latter is even more and may reach about 0.0272 $/kWh, but the annual solar contribution, relatively to that installation site, allows about 18.45 million $ of fuel saving and avoidance of 0.89 million ton of CO2 emission over 30 years of operation. operation. 

The main goal of this study is to determine the aerodynamic performance and to characterize unsteady flows in a high-speed high-reaction pre-whirl axial flow fan. The pressure waves’ main diametrical modes where two blades interact with two vanes and their sequences are predicted. There are mainly two mechanisms of IGV-rotor interactions identified; the first is attributed to the potential effect whereas the second is due to the wake-blade interaction and the advection of wake mixing into the blades’ passages. Both effects are dependent on the circumferential positions of blades and the axial inter-distance between IGV and rotor. The time mode analyses of pressure fluctuations recorded from different monitor points are determined and the frequencies of prevailing modes and those related to the vortical flow structure through the components are also identified. The understanding of vanes and blade rows interactions at various axial inter-distances is an important step in determining the beneficial and detrimental effects on the design of high performance axial fan stage.